Telephone receiver



Aug. 21, 1928. 1,681,161

N. BALDWIN TELEPHONE RECEIVER Filed Aug. 29, 1925 W 3 INVENTOR Patented Aug. 21, 1928.

NATHANIEL BALDWIN, OE EAST MILL CREEK, UTAH.

TELEPHONE RECEIVER.

Application filed August 29, 1925. Serial No. 53,350.

' The present invention, appertains to telephone receivers and embodies a general principle disclosed in my former Patent No. 957,463, issued May 10, '1910, namely, the

principle 0 using an armature actuated by a surrounding coil or coils and acted upon at its ends by four polepiece limbs arranged alternately on opposite sides of the armature as illustrated in Fig. 13 of the above mentioned patent.

3 The objects of the present invention are to provide a convenient arrangement and magnetic connection of such polepieces. 'To provide suitable resilient supports for the armature and suitable means to transmit the movements of the armature. to a dia hragm or other sound producing agent or e ement.

I attain these and other objects by the mechanism illustrated in the accompanying 2 0 drawing in which Fig. 1 is a back view of: the

instrument with part of the shell cut away; I

Fig. 2 is emotion of the instrument along the line AB of Fig. 1; and Fig. 3 is a partial sec-.

tion of theinstrument' along'the line CD of Fig. 1, showing parts in elevation with one magnet removed.

In the several figures of the drawing-numera1-1 designates a baseplate to which the magnets 2 and 3 are secured bymeans of- 30. screws, solder or otherwise. These magnets are substantially semicircular in shape with abutting ends straightened to fit the poleieces 4 and 5 which are secured to the magnet b means of screws as shown.

The spool 6 is a structure simllar to that shown in m crum provi ed in it. 7 It is-inclosed and held in position by the pole ieces 4 and' 5. These olepieces are formed y bending flat bars of iron into U-shaped pieces and cutting away the .upper part of one-limb and the lower part of the other. p gether over the'spool and projecting edges- 7, 7 and 8, 8 formed on the limbs of the polepieces engage the straight edges of the spool 6 and hold it in proper position, and the proper spacing between the polepieces is also maintained.

The terminals of the coil which is wound upon the spool are connected to the cord tips 10, 11, by means of bindlng posts or connections of any convenient design.

A shell or casing 12' incloses these several parts and the base plate 1 is held upon the casing 12 by means of the clamping ring 14.

passes through the aperture An armature 15 -former patent but has no ful- The polepieces then fit tov in the spool 6 and between the limbs of the polepieces 4 and 5 withouttouching either and is supported in proper position within the spool 6 and between the limbs of the polepieces 4 and '5 by means of small strings or wires 16, 16 which-pass through. slots in the autism: the armature 15 and are held taut by brackets 17,17 to which the ends of the strings or wires 16, 16 are secured. The brackets 17, 17 whichmay be secured to one or both of the polepieces. 4 and 5 are slotted near one end as shown and screws '18, 18

tapped into the brackets are adapted to spread the slots more or less and thus adjust the tension of the strings or wires 16, 16.

Thediaphragm 13, which is made rig'idby I a special shape is supported from the armature 15 by the connecting rods 19 and vibrates as'a whole in connection with the armature. I claim 1. A telephone receiver comprising an ars mature mounted on tensioned -members, and adapted to vibrate transversely, an actuating coil disposed around said armature, 9. diaphragm and means to transmit the motion of said armature to said diaphragm, a diaphragm carried by said armature.

2. -A telephonereceiver comprising an armature mounted on tensioned members, and adapted to vibrate transversely, an actuating coil disposed around said armature, ,a dia-, phragm and connecting rods to transmit the motion of said armature to said diaphragm.

3. A telephone receiver comprising an armature mounted o-ntensioned members, and adapted to vibrate transversely, an actuating coil disposed around said armature, four polepiece limbs acting upon the ends of said armature, two polepiece limbs of like polarity acting upon opposite ends and upon opposite sides of said" armature and the other two polepiece limbs of opposite polarity from the first mentioned polepiece limbs acting upon the said armaturein alternate positions to the first mentioned polepiece limbs, a diaphragm and connecting rods to transmit the motion of said armature to said diaphragm.

4."A telephone receiver comprising an armature, surrounded by an actuating coil and adapted to vibrate transversely, stretched members resiliently supporting said armature, a diaphragm and connecting rods to transmit the motion of said armature to said diaphragm.

5. A telephone receiver comprising an armature surrounded by an actuating coil,

and adapted to vibrate transversely, stretched members resiliently supporting said armature, four polepiece limbs acting upon the ends of said armature, two polepiece limbs of like polarity acting upon opposite ends and upon opposite sides of said armature and the other two polepiece limbs of opposite polarity from the first mentioned polepiece limbs acting upon the said armature in alternate positions to the first mentioned polepiece limbs, a. diaphragm and connecting rods said armature by means of said connecting rods and adapted to vibrate with said'armature.

8. A telephone receiver comprising an armature surrounded by an actuating coil, and adapted to vibrate transversely, stretched wires resiliently supporting said armature, four polepiece limbs acting upon the ends of said armature, two polepiece limbs of like polarity acting upon opposite ends and upon opposite sides of said armature and the other two polepiece limbs of o posite polarity from the first mentioned p0 epiece limbs acting upon the said armature in alternate positions to the first mentioned polepiece limbs, connecting rods; a diaphragm mounted upon said armature by means of said connecting rods and adapted to vibrate with said armature.

9. In combination an armature, tensioned resilient supporting means whereon saidarmature is mounted, an actuating coil disposed around said armature, a diaphragm, and means to connect said armature to said diaphragm.

NATHANIEL BALDWIN. 

